The goal of this project is to develop a framework for surgeons to interact with patient-specific geometries to simulate cardiac reconstruction procedures. There is a need for image-based simulation and modeling because current management of congenital heart defects remains a subjective and qualitative process and surgical planning for reconstruction is often based on empirical knowledge. We believe that intuitive interfaces to physical models based on quantitative, patient-specific information would refine surgical decision-making and thus optimize the physiological outcomes of cardiovascular procedures. This will be achieved by providing quantitative information through simulation to permit the clinician to evaluate the physiological state of the patient and plan surgical procedures. Our goal is to enable surgeons to analyze various surgical options and perform physiological "what if?" analysis of proposed reconstructions through a real time interaction using a haptic interfaces to directly shape the geometry used for the simulation. [unreadable] [unreadable] [unreadable]